基于CRT的(3,L)-QC-LDPC码构造

摘要

对于任意行重L,利用完全确定的方式构造出一类围长为8的(3,L)-LDPC码作为分量码1,构造可快速编码的LDPC码作为分量码2,利用分量码1和分量码2,并结合中国剩余定理(CRT)构造出一类围长至少为8的合成QC-LDPC码.该方法构造出来的码字同时具备以上两种特性.仿真结果表明,所构造的码字性能与基于IRCMS算法构造的QC-LDPC码相比,有略微提升,且具有快速编码特性,编码复杂度更低;与具有双对角结构的阵列码相比,性能有了明显提升.在误码率达到10-4时,码字性能大约提高了0.3 dB;与PEG-CRT-LDPC码相比,所构造的码字在低编码复杂度的基础上性能有所提升.%For any row weight L,a new family of(3,L)-regular Low-Density Parity-Check(LDPC)codes is proposed explicitly with girth eight as the first component code.Another Low-Density Parity-Check(LDPC)codes with the capacity of fast encoding is proposed as the second component code. Employing these new codes in the construction method of Chinese Remainder Theorem(CRT), a novel class of compound QC-LDPC codes is presented with both girth at least eight and very flexible code lengths.The proposed codes have the above two characteristics.Simulation results show that compared with QC-LDPC code constructed by IRCMS algorithm,the proposed codes have comparable or even better per-formance,while the encoding complexity is lower;moreover,the proposed codes outperform the array code with dual-diagonal parity structure about 0.3 dB gain at BER of 10-4with the capacity of fast encoding.Compared with PEG-CRT-LDPC codes,the proposed codes have better performance while the encoding complexity is lower.